September 24, 2012

Erosion Of Great Barrier Reef Raises Conservation Questions

As anyone who follows politics knows, public policy is a process that can take years or decades to hammer out, especially when it comes to certain issues. Unfortunately, the forces of nature are always in a state of flux, which can make it difficult to develop policy around them.

With this in mind, Australian researchers set out to study the effects of climate change and temperature dynamics around the Great Barrier Reef (GBR) and its critical protected areas. They were able to record and analyze major changes around the reef within the past 25 years.

“When we looked back at satellite data collected since 1985, we found evidence that most of the regions of the GBR are changing significantly, in terms of sea surface temperature — especially in the southern part of the reef,” said Natalie Ban, who is the lead author of a report which appeared online in the journal Conservation Biology.

Conservationists are particularly worried about coral bleaching and die-off that can occur because of temperature swings.

“Risk of coral bleaching increases with higher water temperatures,” Ban said. “Across the whole reef we found water temperatures increasing by an average of 0.2 of a degree over a quarter of a century — but the increase was significantly more in some areas."

“For example, off Rockhampton the water has warmed by about half a degree over the last 25 years,” she added.

After pouring over years of data, the researchers formulated conservation targets and objectives based on higher temperature fluctuations. They also posed questions for officials about improving coral reef protections.

“Some people think we ought to have the highest levels of protection for areas that are changing the least, so they remain as refugia to recharge the surrounding reef areas,” Ban said. “Others argue the opposite — that the greatest protection should be afforded to the most vulnerable areas.”

“Others still argue that Green Zones and other types of restrictions should migrate geographically along with the climate — that their boundaries should change gradually in line with trends in water temperature and reef biology,” she added.

“Our aim in publishing this paper on what is actually happening is to stimulate and inform this discussion, so that we can come up with the best and most flexible system for managing the GBR through what will undoubtedly be momentous environmental change.”

Currently, the Green Zones are viewed as successful since they have been shown to increase the fish population, and Australian Environment Minister Tony Burke rolled out a new network of marine protected areas earlier this year.

However, a robust debate is currently underway in Australia as business interests fight against restrictions, while conservationists say the protections do not go far enough.

Ban said her team´s study adds to that debate by making all parties involved more informed.

“We need to understand what we are managing for, to have the best management plan,” she explained.

Many experts consider Australians the foremost experts on the coral reef ecosystem and as a leader in public policy surrounding these fragile, but important habitats.